Excavating buckets are used extensively in the construction and mining industries. Buckets are used with a variety of different excavating apparatus, such as back hoes, power shovels, front end loaders, dragline equipment, etc. Although these buckets have many differences, they are generally formed with a rear wall, side walls and a bottom wall. The walls cooperatively define an open front and a cavity for gathering earthen material and moving it to a dump site. The bottom edge of the open front is defined by a forward lip of the bottom wall. The lip is intended to engage the ground for collection of the material into the bucket's cavity. The lip may be formed to have a linear or arcuate shaped edge, or formed to have a particular configuration (such as V-shaped) to suit the desired operation. Similarly, the front edges of the side walls are also adapted to engage the ground.
Attachments are commonly mounted on the lip and the front edges of the side walls to increase the effectiveness and durability of the buckets. These attachments typically include teeth, shrouds and wings. The teeth project forwardly of the lip to disrupt the material for enhanced collection of the material into the cavity. The shrouds are positioned in between the teeth and are generally provided with an inclined surface to improve the collection of the material into the bucket. The wings are attached to the front edges of the side walls in general proximity with the lips. In any event, the attachments protect the bucket against undue wearing. As a result, only the attachments normally need replacement when the front of the bucket becomes worn; thus, prolonging the usable life of the larger and more expensive lip and side walls.
In most cases, a tooth is formed of an adapter and a point. The adapter is attached to the lip and serves as a mount for the point. The point is a wear element and forms the forward portion of the tooth that engages the ground. The point may be attached to the adapter in a number of different ways. Examples of such arrangements are disclosed in U.S. Pat. Nos. 4,231,173 to Davis, 4,335,532 to Hahn et al., and 4,727,663 to Hahn. As a result of this two-part construction, replacement of only the point is generally needed when the tooth becomes worn.
The attachments are each formed with a forward working portion and a rearward mounting portion. The forward working portions of the adapters include structures to facilitate attachment of the points. The forward working portions of the shrouds and wings typically include surfaces designed to engage the worked material and guide it into the bucket. The rearward portions of the attachments are typically bifurcated to define a pair of legs. The bifurcated legs straddle the lip so that one leg lies against the interior of the bucket and one leg lies against the exterior thereof. In some bifurcated designs one leg extends only a very short distance rearward of the lip edge. Alternatively, some designs have only one leg that lies against the interior of the bucket. In any event, the legs generally have hollow central portions to provide greater weight reduction. As a result of this hollowed construction, a peripheral rim is defined around the legs for engaging the lip.
The attachments can be secured to the bucket in a number of different ways. For instance, the attachments may be secured through the use of a wedge locking system, such as disclosed in U.S. Pat. Nos. 4,267,653 to Hahn et al. and 4,271,615 to Jones. Alternatively, the attachments may be secured to a lip by welding or bolting.
The lips and side walls of different buckets are not generally uniform in shape and are often manufactured with leading beveled edges which are oriented at different inclinations. The leading beveled edge is an inclined surface at the forward end of the lip or side wall, which lies in a plane intersecting the exterior and interior surfaces. The inclination is upwardly and rearwardly with respect to the outer surface. Hence, irrespective of the type of mounting arrangement used to secure the attachment to the bucket, a unique attachment is ordinarily required for each different bucket to accommodate the different configuration. This special manufacturing of the attachments not only increases fabrication costs, but also creates a substantial inventory for users and distributors.